Ahmed, T.
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Dimuon Production in 800 GeV Proton Nucleus Collisions

Brown, C.N. ; Cooper, W.E. ; Finley, D. ; et al.
Phys.Rev.Lett. 63 (1989) 2637-2640, 1989.
Inspire Record 288346 DOI 10.17182/hepdata.20031

A measurement of continuum dimuon production in proton-copper collisions at 800-GeV incident energy is presented. The dimuons observed in this experiment cover the mass range from 6.5 to 18 GeV near y=0 in the proton-nucleon center-of-momentum frame. Scaling forms of the cross section for the continuum are compared with the results of other experiments in the context of the parton model and quantum chromodynamics. The present limitations of such scaling comparisons are discussed.

1 data table
Table 1

No description provided.


Experimental Evidence for the Nonabelian Nature of {QCD}

The AMY collaboration Park, I.H. ; Schnetzer, S. ; Green, J. ; et al.
Phys.Rev.Lett. 62 (1989) 1713, 1989.
Inspire Record 276619 DOI 10.17182/hepdata.20045

We present evidence for the non-Abelian nature of QCD from a study of multijet events produced in e+e− annihilations from √s =50 to 57 GeV in the AMY detector at the KEK storage ring TRISTAN. A comparison of the three-jet event fraction at TRISTAN to the fraction of the DESY storage ring PETRA shows that the QCD coupling strength αs decreases with increasing Q2. In addition, measurements of the angular distributions of four-jet events show evidence for the triple-gluon vertex.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Charm photoproduction

The Tagged Photon Spectrometer collaboration Anjos, J.C. ; Appel, J.A. ; Bean, A. ; et al.
Phys.Rev.Lett. 62 (1989) 513-516, 1989.
Inspire Record 289318 DOI 10.17182/hepdata.20043

We present results on the photoproduction of 10 000 charmed particles from the 108 recorded triggers of Fermilab experiment E691. The total cross section for the photoproduction of D0 and D+ particles (and antiparticles) for xF>0.2 is measured to be 3.88±0.06±0.40 μb/Be nucleus at 〈Eγ〉=145 GeV. We have also measured the relative production of different charmed particles, their pT2 and xF distributions, and the energy dependence of the total charm cross section. The mean pT2 is 1.16±0.04 GeV2/c2 and the ratio of charm cross sections at 200 and 100 GeV is 1.96±0.24. Results of fits to the xF distribution are also reported.

12 data tables
Table 1

D0/AD0 cross section from K-PI+/K+PI- decay mode.

Table 2

D+/D- cross section from K-2PI+/K+2PI- decay mode.

Table 3

D*+/D*- cross section from D0<K-PI+>PI+ + CC decay mode.

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RESONANCE PATTERN OF LOW MASS MUON PAIRS PRODUCED IN 38-GEV/C PI- C INTERACTIONS.

The RISK collaboration Bannikov, A.V. ; Bohm, J. ; Choe, Song Hek ; et al.
DUBNA JINR - 89-486 (89,REC.OCT.) 14p, 1989.
Inspire Record 286947 DOI 10.17182/hepdata.39438

None

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


MEASUREMENTS OF D (SIGMA) DE (T) IN COLLISIONS OF LIGHT NUCLEI AT S(NN)**(1/2) = 31.5-GEV

The AXIAL FIELD SPECTROMETER collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 231 (1989) 359-364, 1989.
Inspire Record 287781 DOI 10.17182/hepdata.29771

Calorimeter measurements of dσ de t for pp, dd, pα , and αα collisions at S nn =31.5 GeV are presented for the pseudorapidity interval | η cm | ⩽ 0.7, extending over eight decades to E t ⩾ 30 GeV. The data are compared with models that predict nuclear cross sections directly from pp data, under the assumption of independent nucleon scatters.

1 data table
Table 1

The distributions are fitted D(SIG)/D(ET)=CONST*ET**POWER*EXP(-SLOPE*ET).


MEASUREMENT OF ANALYZING POWER IN FORWARD ANGLE FOR ELASTIC p d SCATTERING AT 3.5-GeV

Ohmori, C. ; Horikawa, N. ; Ishida, Y. ; et al.
Phys.Lett.B 230 (1989) 27-30, 1989.
Inspire Record 277083 DOI 10.17182/hepdata.29770

The analyzing power for elastic pd scattering at 3.5 GeV has been measured in the region 0.1⩽−t⩽1.5 (GeV/ c ) 2 , using the polarized proton beam at KEK. The angular distribution shows a behavior similar to that in the lower energy region. It is reproduced fairly well by the predictions of a multiple scattering model based on the Glauber theory.

1 data table
Table 1

No description provided.


Measurements of the $u$ Valence Quark Distribution Function in the Proton and $u$ Quark Fragmentation Functions

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.
Nucl.Phys.B 321 (1989) 541-560, 1989.
Inspire Record 276746 DOI 10.17182/hepdata.33218

A new determination of the u valence quark distribution function in the proton is obtained from the analysis of identified charged pions, kaons, protons and antiprotons produced in muon-proton and muon-deuteron scattering. The comparison with results obtained in inclusive deep inelastic lepton-nucleon scattering provides a further test of the quark-parton model. The u quark fragmentation functions into positive and negative pions, kaons, protons and antiprotons are also measured.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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MEASUREMENTS OF THE e+ e- TOTAL HADRONIC CROSS-SECTION AND A DETERMINATION OF M(Z) AND LAMBDA (MS)

The AMY collaboration Mori, T. ; Nozaki, T. ; Blanis, D. ; et al.
Phys.Lett.B 218 (1989) 499-507, 1989.
Inspire Record 276653 DOI 10.17182/hepdata.29847

The total cross section for e + e − annihilation into hadrons has been measured for CM energies ranging from 50 to 57 GeV. We fit the predictions of the standard model to these measurements and those at lower energies. The mass of the Z 0 boson, M Z , and the QCD scale parameter, Λ MS , are derived from the fit. The results are M Z =88.6 −1.8 +2.0 GeV/ c 2 , and Λ MS =0.15 −0.11 +0.16 GeV .

1 data table
Table 1

No description provided.


A High Statistics Measurement of the Proton Structure Functions F(2) (x, Q**2) and R from Deep Inelastic Muon Scattering at High Q**2

The BCDMS collaboration Benvenuti, A.C. ; Bollini, D. ; Bruni, G. ; et al.
Phys.Lett.B 223 (1989) 485-489, 1989.
Inspire Record 276661 DOI 10.17182/hepdata.12557

We present results on a high statistics study of the proton structure functions F 2 ( x , Q 2 ) and R = σ L / σ T measured in deep inelastic scattering of muons on a hydrogen target. The analysis is based on 1.8 × 10 6 events after all cuts, recorded at beam energies of 100, 120, 200 and 280 GeV and covering a kinematic range 0.06 ⩽ x ⩽ 0.80 and 7 GeV 2 ⩽ Q 2 ⩽260 GeV 2 . At small x , we find R to be different from zero in agreement with predictions of perturbative QCD.

105 data tables
Table 1

THE AVERAGE VALUES OF Q**2 AT EACH OF THE X VALUES LISTED IN THIS TABLE ARE 15,20,20,25,30,35,40,45,50,50.

Table 2

R=SIG(L)/SIG(T) IS TAKEN TO BE ZERO.

Table 3

R=SIG(L)/SIG(T) IS TAKEN TO BE ZERO.

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Transverse Momentum Distributions of Neutral Pions From Central and Peripheral $^{16}$O + Au Collisions at 200-a/{GeV}

The WA80 collaboration Albrecht, R. ; Awes, T.C. ; Baktash, C. ; et al.
Z.Phys.C 47 (1990) 367-376, 1990.
Inspire Record 276573 DOI 10.17182/hepdata.15159

The production of neutral pions by the interaction of 200A·GeV p and16O projectiles with a Au target has been studied in the pseudorapidity range 1.5≦η≦2.1. Transverse momentum spectra have been measured between 0.4 GeV/c and 3.6 GeV/c and their dependence on the centrality of the collision has been investigated. The peripheral-collision spectra display a marked change of slope with a hard component starting at about 1.8 GeV/c, in contrast to central-collision data. The data are discussed in comparison to p+p and α+α data from the ISR.

4 data tables
Table 1

Data obtained with minimum bias trigger conditions.

Table 2

Data obtained with minimum bias trigger conditions.

Table 3

Data for central collisions.

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